This invention relates generally to an apparatus for forming wrapped food products which continuously produces the product, and more particularly to a double extrusion apparatus.
Food products having a central filling material including but not limited to Chinese "pot stickers", tamales, ravioli, dumplings, pierogi, filled donuts, soft center candies, and the like, are well known. Numerous devices have been developed in an attempt to produce such products quickly and efficiently.
U.S. Pat. No. 4,251,201, dated Feb. 17, 1981 to Krysiak discloses an extrusion apparatus useful for the production of such a food product. This apparatus includes inner and outer conduits through which materials are extruded toward an iris valve. Food material is sequenced through a conduit operatively connected to the iris valve, wherein the food product is formed. Movement of the iris valve to open and closed positions is sequenced by an assembly which controls movement of the food material to the valve. In this regard, the apparatus fails to provide for continuous formation of a wrapped food product.
U.S. Pat. No. 3,778,209, dated Dec. 11, 1973 to Wallace et al, discloses a machine for producing food products having an extruded filler material and an extruded outer covering. Included is a means for intermittently stopping the flow of the filler product in such a manner that uniform, intermittent extrusion is maintained; and for slicing the extruded outer material between portions of the intermittently extruded filler material. A conveyor belt and wheel with cutting blades are provided. The final food product is formed by intermittently stopping extrusions, and cutting resultant food ribbon to form the desired end product.
Other known apparatus for producing food products include: U.S. Pat. No. 3,234,869, dated Feb. 15, 1966 to Poranbo; U.S. Pat. No. 3,316,833, dated May 2, 1967 to Williams et al; U.S. Pat. No. 2,047,262, dated July 14, 1936 to Gibson et al; and U.S. Pat. No. 1,647,683, dated Nov. 1, 1927 to Bollinger.
It would be desirable to provide an apparatus for forming wrapped food products continuously, without sequencing or intermittently stopping the flow of extruded food material. It would also be desirable to provide an apparatus and method for forming wrapped food products which continuously extrudes, forms, shapes, and seals the final product without intermittent stoppage. It would be a further advancement to provide an apparatus and method for continuously extruding, forming, shaping and sealing a wrapped food product without any waste, and subsequently provide for continuous cooking (to a desired level of cooking) of the wrapped food product.